The present invention relates to a slot array antenna assembly employing a dielectric director mechanism which exhibits the most suitable structure when used as an antenna for marine radars or the like.
In the past, various methods have been proposed in which the vertical plane beamwidth of a slot array antenna is reduced by a dielectric material A typical of these methods is disclosed for example in U.S. Pat. No. 3,234,558. Considering the fact that not only these methods have not been extensively put in practical applications but also even the owner of the patent right of this patent has not realized the merchandizing of the method, the situation appears in a sense due to the fact that the operating principle of this patent was not grapsed sufficiently at the time of its filing. In other words, it is difficult for the method disclosed by the patent to form a beam that can be put in practical use and thus no reduction in the side lobe level is attained.